In 204, the Ptolemaic king Ptolemy IV Philopator died, leaving behind a very young successor, Ptolemy V Epiphanes. The Seleucid king Antiochus III the Great and king Philip V of Macedonia decided to attack the weakened Ptolemaic kingdom, and soon, the Fifth Syrian War broke out in which the Seleucids finally conquered Coele Syria. Macedonian power in the Aegean world also increased, and this was something that the Roman Senate found unacceptable. It sent envoys to Greece to create an anti-Macedonian coalition, a measure that Philip interpreted as a sign of Roman weakness - after all, the Second Punic War was just over, and Rome was war-worn indeed. When Philip refused to give up its conquest, the Senate and Assembly declared war, and in 200, the legions crossed the Adriatic Sea.
The first Roman commander achieved several small successes, sufficient to bring the Aetolian League to the Roman side, and isolating Macedonia. In 197, Titus Quinctius Flamininus received the command, and Philip opened negotiations. The Roman understood that the Macedonian leader was seriously weakened, and demanded the evacuation of Thessaly, which had been Macedonian since the days of Philip II, more than a century and a half ago. This demand was unacceptable, war was renewed, and in June 197, the two armies met at Cynoscephalae, north of Pharsalus, along the road to Larisa, in Thessaly.
It was to become a classic battle, which not only proved that Rome was the stronger side, but also that the Macedonian phalanx was unable to adapt itself to the terrain, whereas the Roman legions were more flexible. The decisive maneuver was when a Roman tribune, whose name has not been recorded, turned his troops and attacked the Macedonian phalanx in the rear. It comes as no surprise that the Greek historian Polybius of Megalopolis concluded that Cynoscephalae was the best example to show the flexible legions were superior to the phalanx.note
Plutarch of Chaeronea describes the battle in the following words:
Towards morning on the following day, after a mild and damp night, the clouds turned to mist, the whole plain was filled with profound darkness, a dense air came down from the heights into the space between the two camps, and as soon as day advanced all the ground was hidden from view. The parties sent out on either side for purposes of ambush and reconnaissance encountered one another in a very short time and went to fighting near what are called the Cynoscephalae ["dogs' heads"]. These are the sharp tops of hills lying close together alongside one another, and got their name from a resemblance in their shape. As was natural on a field so difficult, each party sending out aid from their camps to those who from time to time were getting the worst of it and retreating, until at last, when the air cleared up and they could see what was going on, they engaged with all their forces.
With his right wing, then, Philip had the advantage, since from higher ground he threw his entire phalanx upon the Romans, who could not withstand the weight of its interlocking shields and the sharpness of its projecting pikes; but his left wing was broken up and scattered along the hills, and Titus, despairing of his defeated wing, rode swiftly along to the other, and with it fell upon the Macedonians. These were unable to hold their phalanx together and maintain the depth of its formation (which was the main source of their strength), being prevented by the roughness and irregularity of the ground, while for fighting man to man they had armor which was too cumbersome and heavy.
For the phalanx is like an animal of invincible strength as long as it is one body and can keep its shields locked together in a single formation; but when it has been broken up into its parts, each of its fighting men loses also his individual force, as well because of the manner in which he is armed as because his strength lies in the mutual support of the parts of the whole body rather than in himself.
This wing of the Macedonians being routed, some of the Romans pursued the fugitives, while others dashed out upon the flank of the enemy who were still fighting and cut them down, so that very soon their victorious wing also faced about, threw away their weapons, and fled. The result was that no fewer than 8,000 Macedonians were slain, and 5,000 were taken prisoners. Philip, however, got safely away, and for this the Aetolians were to blame, who fell to sacking and plundering the enemy's camp while the Romans were still pursuing, so that when the Romans came back to it they found nothing there.note
The Roman victory was hailed as the "liberation of Greece", but the Greeks never fully understood that according to Roman law, a freed person still had obligations to the man who had released him. The first half of the second century saw several conflicts between the Greeks and Romans, which culminated in the sack of Corinth and the annexation of Greece in 146.
According to the historian Appian of Alexandria, the dead at Cynoscephalae still lay unburied in 191.note
- N.G.L. Hammond, "The Campaign and Battle of Cynoscephalae in 197 BC" in Journal of Hellenic Studies 108 (1988) (identifies the battlefield as a site between the small villages Zoodochos and Chalciades)